371 oil valley plugs

papadoc · 04-11-2008, 02:37 PM

I recently had a machine shop rebuild my 371 engine. After installing and lubricating the engine with a spare distributor stem I fired her up. I'm not getting hardly any oil to the drivers side oil galley. I suspect that they failed to replace a oil valley plug somewhere probably on the rear driver side and no flow resistence is had. Just where are these plugs located and how do you get to them without pulling the engine. I can't find any schmatics on this engine anywhere and the machine shop relocated to another state. Any help would be appreciated. papadoc

marcar1993 · 04-27-2008, 06:37 PM

They'd probably be in the valley under the intake. If that's were they are, you'd have to take the intake off to get to them. I'm not to familiar with the early motors so I'll stop there..

59-59-59 · 04-27-2008, 11:01 PM

I cant believe I wasted MY time since YOU already posted this 2 weeks ago...Remember???

Thanks for the comeback - I believe I've found the problem by discussing the problem with an old time mechanic. On the driver side rear oil galley there are two plugs. One is an outer press-in type on the the rear block area and the other is a inner 3/8 inch pipe plug with a spit hole to lube the distributor/cam gear. If the inner plug is not re-installed during re-assembly the oil runs throught the galley and dumps back into the pan. No back pressure is had to lube the lifters on the drivers side mainly and also not enough pressure to force oil up to the rockers. To check this out pull the distributor and insert an old revamped distributor shaft, spin the oil pump with a drill while looking down with a lite to the rear cam gear and if a large volumn of oil is being dispersed then the rear inner plug is missing. If the plug is there only a minimal amount is dispersed thru the spit hole. I checked this out yesterday and sure nuff no rear inner plug apparent thus no back pressure for proper lubrication. Unfortunately the only way to get to the inner plug is to pull the engine, remove the outer plug to get to the inner plug and install a inner plug with a spit hole drilled in the center. Needless to say me and a machine shop will have strong words very shortly. I appreciated all parties for their help in trying to resolve this problem and at least we all now know a simple way to check this out. I'll have the engine out come evening. Thanks again - papadoc

04-11-2008, 02:37 PM	#1 (permalink)
papadoc Junior Member Join Date: Apr 2008 Posts: 6	371 oil valley plugs I recently had a machine shop rebuild my 371 engine. After installing and lubricating the engine with a spare distributor stem I fired her up. I'm not getting hardly any oil to the drivers side oil galley. I suspect that they failed to replace a oil valley plug somewhere probably on the rear driver side and no flow resistence is had. Just where are these plugs located and how do you get to them without pulling the engine. I can't find any schmatics on this engine anywhere and the machine shop relocated to another state. Any help would be appreciated. papadoc

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04-27-2008, 06:37 PM	#2 (permalink)
marcar1993 Senior Member Join Date: Apr 2007 Posts: 126	They'd probably be in the valley under the intake. If that's were they are, you'd have to take the intake off to get to them. I'm not to familiar with the early motors so I'll stop there..

04-27-2008, 11:01 PM	#3 (permalink)
59-59-59 Senior Member Join Date: Sep 2006 Posts: 166	I cant believe I wasted MY time since YOU already posted this 2 weeks ago...Remember??? Thanks for the comeback - I believe I've found the problem by discussing the problem with an old time mechanic. On the driver side rear oil galley there are two plugs. One is an outer press-in type on the the rear block area and the other is a inner 3/8 inch pipe plug with a spit hole to lube the distributor/cam gear. If the inner plug is not re-installed during re-assembly the oil runs throught the galley and dumps back into the pan. No back pressure is had to lube the lifters on the drivers side mainly and also not enough pressure to force oil up to the rockers. To check this out pull the distributor and insert an old revamped distributor shaft, spin the oil pump with a drill while looking down with a lite to the rear cam gear and if a large volumn of oil is being dispersed then the rear inner plug is missing. If the plug is there only a minimal amount is dispersed thru the spit hole. I checked this out yesterday and sure nuff no rear inner plug apparent thus no back pressure for proper lubrication. Unfortunately the only way to get to the inner plug is to pull the engine, remove the outer plug to get to the inner plug and install a inner plug with a spit hole drilled in the center. Needless to say me and a machine shop will have strong words very shortly. I appreciated all parties for their help in trying to resolve this problem and at least we all now know a simple way to check this out. I'll have the engine out come evening. Thanks again - papadoc